Ecole MACS 2015

Module "Formalismes et diagnostic des systèmes à événements discrets"

Introduction aux SED, langages et automates

présentation (pdf)

Laurent Piétrac

Ampère, INSA Lyon

Introduction aux réseaux de Petri

présentation (pdf)

Isabel Demongodin

LSIS, Université de Marseille

Méthodes et outils de l'algèbre max-plus pour les SED

présentation (pdf)

Bertrand Cottenceau, Mehdi Lhommeau, Sébastien Lahaye

LARIS, Université d'Angers

Diagnostic des systèmes à événements discrets

Alessandro Giua (LSIS, Marseille), Armand Toguyeni (LAGIS, Lille), Dimitri Lefebvre (GREAH, Le Havre) et Yannick Pencolé (LAAS, Toulouse)

In testing problems, a topic of great interest is that of state identification, i.e., estimating the state of a discrete event system. Among the different approaches that have been presented in the literature  we consider those based on synchronizing sequences, i.e., sequences that drive the system to a known final state regardless of the initial one and do not require the observation of the system’s outputs. For automata models the problem of computing such sequences has been completely solved but its complexity is polynomial in the number of states.

In this talk I discuss some recent results for the computation of synchronizing sequences on discrete event systems modeled by synchronized Petri nets. It will be shown that the approaches based on Petri nets offer significant computation advantages with respect to the automata based approaches: in fact they may exploit the knowledge of the net structure and do not require the exhaustive enumeration of its state space. Furthermore, I also show how these techniques can be extended to encompass systems with an infinite state space.